Typewriting-machine



w. A. LORENZ.

TYPEWRITING MACHINE.

APPHCATION FILED APR. 22, I919.

1,344,304: Patented June 22, 1920.

UNITED STATES PATENT OFFICE.

WILLIAM A. LORENZ, or HARTFORD, CONNECTICUT, ASSIGNOR 'ro UNDERWOOD I TYPEWRITER COMPANY, or NEWYORK, N. Y., A CORPORATION or DELAWARE.

TYPEWRITING-MACHIN E.

Application filed 'April 22,

To all whom it may concern.

Be it known that I, IVILLIAM A. LORENZ, a citizen of the United States, residing in Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Typewriting-Machines, of which the following is a specification.

This invention relates to writing machines of the Underwood type, in which the typebearing end of the type-bar is given whiplike action, as set forth in the Manning Patent No. 612,858.

The tendency of the long thin type-bar to chatter and make repeated impressions upon the work-sheet is overcome, according to said patent, by interposing a rigid abutment or stop-segment near the pivot end of the type-bar, so that each of the type-bars may be arrested thereby, while the type is nearing the platen. Since the type-bars move with considerable force, the upper part thereof is whipped or sprung sufliciently to deliver the type blow on the work-sheet. The abutment prevents the type from chattering or from striking the sheet repeatedly.

An object of the present invention is to reduce the noise made by the type-bars in striking said abutment or stop-segment.

To this end, the segmental or other form of abutment or stop is made separate from the segment in which the type-bars are pivoted, and is connected to said type-bar segment by a sound-deadening mounting, preferably soft rubber, in such a manner that the stop may perform its function while substantially eliminating the noise of the blows of the type-bars thereon.

In carrying out the invention, there are placed upon the front of the type-bar segment a set of soft rubber cushions, and the type-bar stop is provided with studs which fit holes in said cushions. These cushions preferably form the sole support of the type-bar stop, so that sound vibrations may not be communicated from the stop through any metal connection to the type-bar segment, and also so as to dampen the vibrations of the stop.

Although the studs are made of metal or hard material, and the type-bar segment is provided with soft rubber plugs to match, still, within the scope of the invention, the

Specification of Letters Patent.

Patented June 22, 1920. 1919. Serial No. 291,878.

parts may be reversed and the studs made of soft rubber and the plugs of hard material. Ea ch stud comprises a shank for insertion 1nto a hole or seat in the type-bar stop. The stud itself is made of tapering form, and the hole in the rubber cushion is correspondingly shaped. At its outer end, the

hole is given a wide flaring form, and the bar segment and platen of a machine of the Underwood type, provided with the present improvements, showing the tvpe-bar in printing position.

ig. 2 is a sectional side elevation of the same.

Fig. 3 is an enlarged sectional view of details of the studs which support the stop- :egment, showing the latter in normal posi- Ion.

Fig. 4 is similar to Fig. 3, but shows a type-bar in printing position, and the stopsegment as having been slightly displaced by the type-bar. In Figs. 3 and at, there is slight exaggeration in the form of the stud and in the extent of movement of the stop-segment, in order to make the operation clear. V

In a cast-iron segment 5 are pivoted at 5 radial type-bars 6 carrying type-heads? to strike against a platen 8, the type-bars being key-operated in any usual way, as, for instance, by means of links 9.

'The improved stop 10, which arrests the type-bars in printing position, as in Fig. 2, is made separately from the type-bar segment 5, and has both top and bottom ears 11, through which extend screws 12, which are shouldered against the frame 5, and have heads to retain the stop-segment. These screws pass through holes 13 in the stopsegment 11. The holes are made oversize in order to avoid metallic pommunication between the stop-segment and the type-bar segment.

The stop-segment is mounted upon the type-bar segment by means of a set of studs inch.

15, projecting from the rear face of the stop-segment and having shanks 16 forced or secured in perforations 16 in the stopsegment. Each stud 15 is broad at its base and rapidly tapers to a pointedportion 17,

the taper being preferably in the form of a curve 18. These studs fit intosoft rubber or other elastic cushions 20, which are fitted into holes or seats 20 in the type-bar segment mach cushion has a central perforation for the tip 17 of the stud, the front end of the perforation being flared to correspond generally with the tapering of the stud.

The wall of the outer or forward portion of the opening in the cushion is curved on a radius somewhat less than the radius of the corresponding curved part of the stud which it receives. The stud may therefore settle into the opening in the cushion more or less, according to the compressing effect of the screws 12; and the greater the compressing effect the greater will be the area of the curved wall of the cushion in contact with the curved wall of the stud, thereby offering added resistance to the compressing effect of the screws. Normally the curve of the wall studand the wall of the opening in the cushion are so related that the outer part of the stud does not completely fill the outer part of the cushion opening. This renders the device sensitive, and results in complete absorption of shock and noise when the machine is being operated.

From the foregoing, it will be seen that the curved contours of the stud and cushion at Fig. 3 diverge at the base of the stud, the stud line 21 separating from the cushion line 22 but slightly, approximating in practice not more than a few thousandths of an The curved surface of the cushion resists rearward movement of the stop-segment. The point of divergence at the lines 21, 22 indicates the normal boundary of the resisting surface of the cushion. When,

however, the stop-segment is forced back,

the surfaces 21 and 22 are forced into engagement, thereby increasing theactual resisting surface of the cushion and rendering the same more efficient in sharply arresting the stop-segment, as at Fig. 4. Therefore the efiiciency of the cushion increases With the movement of the stop-segment. In the operation of the machine, the type-bar 6, when it reaches printing position, strikes the face of the stop-segment or plate 10,

and may give to that segment a very slight inward or rearward movement, which is quickly arrested.

If desired, the screws 12 may normally hold the rubber cushions under slight compression; the two screws at the top of the stop-segment structure cooperating with the two screws at the bottom thereof for this purpose, and said screws preferablyhaving head-washers 23 of soft rubber or other non-resonant materal to avoid metal-tometal contact, so that the stop-segrnent is not in engagement with'metalat anypoint.

Thesegrnent may be made of such weight as to have considerable type-bar checking effect because of its own inertia. The slight displacement of the segment at the blow of the type-bar does not allow the type-bar to chatter or strike the paper repeatedly, since the checking of the movement of the stopsegment is prompt, and the return thereof .to normal position is also prompt, owing'to the efficiency of the novel rubber cushion.

Variations may be resorted to within the scope of the invention, and. portions of the improvements may be used without others.

Having thus described my invention, I claim: 1 i

1. In a typewriting machine,the combination with type-bars and a segment or frame on which they are pivoted, of a stop forarresting the type -bars on their printing strokes, a set of soft rubber cushions seated in said segment and having holes, and studs provided upon said stop to fit inthe holes in said cushions.

2. In a typewritins machine, the combination with type-barsand a segment or frame on which they are pivoted, of a stop for arresting the type-bars on their printing strokes, a set of soft rubber cushions seated in said segment and having holes, and studs provided upon said stop to fit in the holesin said cushions, said cushions forming the sole support of said type-bar stop.

3. In a typewriting machine, the combination with type-bars and a segment or frame on which they are pivoted, of a stop for arresting the type-bars on their printing strokes, a set of soft rubber cushionsseated in said segment and having holes, and studs provided upon said stop to fit in the holes in said cushions, said cushions forming the sole support of said typc'bar stop, saidi type-bar stop having holes, and said studs having shanks inserted in the holes.

f. In a typewriting machine, the combination with type-bars and a segment or frame on which they are pivoted,of a stop for arresting the type-bars on their printing strokes, a set of soft rubber cushions seated in said segment and having holes, and studs provided upon said stop to fit in the holes in said cushions, each of said studs made of cushion being formed tofit. 5. In a typewriting machine, the combi" nation with type-bars and a. segment or frame on which they are pivoted, of a stop for arresting the type-bars ontheir printing strokes, a set of soft rubber cushions seated 1n said segment and having holes, and studs .1 provided upon. said stop to fit in the holes in said cushions, the hole in each of sai'd concave tapering form, andthe' hole in its 1 cushions having a wide flaring form, and the base of the stud 'being correspondingly broadened, for the purpose set forth.

6. In a typewriting machine, the combi nation with type-bars anda segment or frame on which they are pivoted, of a stop for arresting the tyfpe-bars on their printing strokes, a set of s t rubber cushions seated in said segment and having holes, and studs provided upon said stop to fit in the holes in said cushions, said stop having holes through which extend shoulder-screws to bear against the type-bar segment-or frame, said screws having heads to retain the stop.

7. In a typewriting machine, the combination with ;type-bars and a segment or frame on which they are pivoted, of a stop.

for arresting the type-bars on their printing strokes, a set of soft rubber cushions seated in said segment and having holes, and studs provided upon said stop to fit in'the holes in said cushions, said stop having holes through which extend shoulder-screws to bear againstxthe type-barsegment or frame,

- said screws ha'vingheads to'retain the stop,

'and said holes being made oversize to avoid contact of the shoulders with thestop, sound-deadening washers provided between said heads and said stop. H 9. In a typewriting-machine, the combi-v nation with type-bars. and a segment or frame on which they are pivoted, of a stop for arresting the type-bars on vtheir printing strokes, a set of soft. rubber cushions seated in said segment and having, ho1 es,and studs said cushions to hold the provided upon said sto to fit in the holes in said cushions, each 0 said studs having a tip portion and a flaring base portion and each of said cushions having a central perforation for the tip of the stud, the perforation being flared to correspond with the tapering base portion of the stud.

10. In a typewriting machine, the combination with type-bars and a segment or frame on which they are pivoted, of a stop for arresting the type-bars on their printing strokes, a set of soft rubber cushions seated in said segment and having holes, and studs provided upon said stop to fit in the holes in said cushions, each of said studs having a tip portion and a flaring, base portion and each of said cushions having a central perforation for the tip of the stud, the perforation being flared to correspond with the tapering base portion of the stud, the flared portion of the opening in the cushion being curved on a radius a little less than the rading of the corresponding flared part of the stu 11. In a ty'pewritingmachine, the combination with type-bars and a segment or frame on which they arepivoted ofa stop for arresting theItype-bars on their printing strokes, a set of soft rubbercushionsseated in said segment and havin holes, studs provided upon said stop to t in the holes in said cushions, each of said studs having a tip portion and a flaring base portion and each of said cushions having a central perforation for-the tip of the stud, the perforation being flared to correspond with the tapering base portion of the-stud, the flared portion of the opening in the cushion being curved on a radius a little less than the radius of the corresponding flared part ofthe stud, and

screws engaging said stop and effective to hold said flared portions of the stud against latter normally under compression. 4

' WILLIAM A. LORENZ.

, Witnesses NELLIE PHOENIX,

- LILLIAN M. Tumor, 

